1995

8.4

2007

4.2

1992

6.9

2008

8.5

2006

6.4

2005

6.8

1993

6.8

1982

5.9

1984

6.1

1985

5.3

1987

6.7

1988

7.1

1986

7.0

2009

6.3

1986

6.2

1997

7.3

1988

5.4

1989

4.9

1993

4.6

2000

7.1